Is it safe to drive with this code?

Driving with P0AFB is not generally recommended. Whilst some vehicles may appear to operate normally in petrol-only mode, abnormal voltage conditions can potentially damage hybrid components or cause unexpected power loss. The vehicle may enter limp mode to protect itself. Refer to our disclaimer and seek professional assessment promptly.

P0AFB may affect MOT outcome if the malfunction indicator lamp is illuminated at the time of test, as dashboard warning lights constitute an MOT failure point. What ultimately matters is whether the light is on during the inspection—see our full disclaimer for guidance.

Roughly how much does it cost to fix?

Costs vary considerably depending on the underlying cause. Wiring repairs or sensor replacement may fall in the low three-figure range, whilst battery management system replacement typically costs mid to high three-figure sums. If individual battery cells or larger portions of the high-voltage pack require replacement, costs can reach four-figure territory, particularly at main dealers. Independent hybrid specialists often charge less than franchised workshops.

Can this code be caused by a faulty sensor rather than an actual battery problem?

Yes, P0AFB can indeed be triggered by faulty voltage sensors or wiring issues that cause incorrect readings, rather than an actual over-voltage condition in the battery pack itself. Proper diagnosis with specialist equipment is essential to distinguish between sensor faults and genuine battery problems before replacing expensive components.

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P0AFB

Powertrain

Hybrid Battery System Voltage High

The hybrid battery pack is reporting voltage readings above the manufacturer's specified threshold, which the powertrain control module has flagged as potentially problematic.

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ⓘ Information only. This page provides general educational information about fault code P0AFB. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.

Recommended next steps

Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.

What does P0AFB mean?

P0AFB is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Hybrid Battery System Voltage High.

This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.

About Electrical & Sensors codes

Codes in the Electrical & Sensors category.

P0AFB is one of 4,010 codes in this category. Browse all Electrical & Sensors codes →

What we know about P0AFB specifically

We record the SAE J2012 standardised definition and the system this code belongs to, but we have not yet published detailed driver-reported symptoms, common causes, or step-by-step diagnostic guidance for P0AFB.

Rather than invent that information by generating generic content from a template, we leave it out. For specific guidance, the most reliable sources are:

•your vehicle's own service manual or manufacturer-specific technical bulletins
•a qualified mechanic with a manufacturer-level diagnostic tool
•a marque specialist familiar with your make and model

Codes nearby

Codes adjacent to P0AFB in the P-code series. Many fault codes appear together with their neighbours because they relate to the same circuit or component.

P0AF8 Hybrid Battery System Voltage

P0AF9 Hybrid Battery System Voltage Unstable

P0AFA Hybrid Battery System Voltage Low

P0AFC Hybrid Battery Pack Sensor Module

P0AFE Hybrid Battery System Voltage Too Low for Voltage Step Up Conversion

P0AFF System Voltage Too Low for Voltage Step Down Conversion

Other Electrical & Sensors codes

Other fault codes in the same system as P0AFB. The ones with detailed guides have plain-English explanations, symptoms, causes, and diagnostic steps.

B1257

Air Temperature External Sensor Circuit Short To Ground Detailed guide

B1363

DBPT Circuit Short To Ground Detailed guide

B2100

Ignition Run/Start Input Circuit Performance Detailed guide

C2000

Steering Angle Sensor Not Calibrated Detailed guide

P0030

HO2S Heater Control Circuit (Bank 1 Sensor 1) Detailed guide

P0031

Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 1 Sensor 1) Detailed guide

Spotted an issue or have something to add? Mechanics, technicians, and drivers who have first-hand experience with P0AFB can submit a correction or expansion. We review every submission before publishing, mechanic submissions are prioritised.

Information only, not professional advice

The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →

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